Identifying landslide risk zones using LiDAR

The application of remote sensing techniques in landslide investigations is rapidly growing as they provide highly accurate 3D terrain information. The high spatial resolution of satellite data opens a new angle to investigate the landslide phenomena. 

Identifying landslide risk zones using LiDAR
lidar for landslide detection

Identifying landslide risk zones using LiDAR

We know LiDAR for revolutionizing the autonomous vehicle industry. It's an instrument equipped with a laser, a scanner, and a GPS. But do you know that LiDAR has many more applications other than guiding autonomous vehicles, and agriculture monitoring? LiDAR scanning is also found to be useful for landslides detection. 

What is a Landslide?

Landslide is a common geological event that can be defined as a downslope movement or transport of soil layer and rocks. Along with some natural phenomena, some human-made activities are also involved in this disaster, such as deforestation, construction with a weak foundation, construction in landslide-prone areas or hilly areas, underground pipelines, etc.

Landslide investigation

The application of remote sensing techniques in landslide investigations is rapidly growing as they provide highly accurate 3D terrain information. The high spatial resolution of satellite data opens a new angle to investigate the landslide phenomena. 

Sensor electronics have advanced to the level that they are now affordable and reachable for various studies and experiments. Techniques like Interferometric Synthetic Aperture Radar (InSAR) and LiDAR are capable of investigating displacements over an area and identifying the landslide's condition.

An advantageous high-resolution digital elevation model (HRDEM) is usually prepared using high-density information obtained from LiDAR data. This model is useful in landslide investigation and mitigation.

Application of LiDAR in landslide studies

Since the geomorphic features are not always scale-dependent, a LiDAR analysis is suitable for debris-flow analysis. Michael Jaboyedoff et al. .2012 characterized LiDAR applications for landslide investigation in their study "Use of LiDAR in landslide investigations: a review." The classification of LiDAR applications in 

Landslide studies, according to them, is as follows: 

Landslide: the steps for landslide monitoring start with mapping geomorphic features for landslide characterization and detection. Hazard assessment and susceptibility mapping are used as support, and HRDEM modeling is the final result. 

Old modeling tools and techniques are not capable of handling a large volume of 3D information density. HRDEM provides accurate landslide modeling and enhances geomorphic characterization. In the end, the surface displacement and volume is monitored to measure the extent of the shift. 

Rockfall: rockfall detection also starts with landslide detection. The characterization in rockfall is done by the rock face imaging and calculation of discontinuous orientation. A Model using high DEM for trajectory modeling then monitors surface displacements. Finally, the Quantification of rockfall activity is done on a volume basis.

Debris-flow: Integrating High-density LiDAR data, sediment budgeting, and monitoring of morphologic changes in the channel can be done easily. 

How is LiDAR data useful?

LiDAR data, with RGB colors (which could be achieved from optical cameras), can provide better results. The hyperspectral cameras merged with LiDAR data gives additional information regarding the characteristics of rocks. 

Also, the helicopter-based LiDAR sensors can be utilized to monitor the vertical cliffs. A lot of information can be derived using LiDAR, and early alert systems can be set for emergencies. 

LiDAR has many uses in different sectors. When technology is used for hazard monitoring, disasters like landslides, slide away without damaging lives and property. 

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